One specialized type of imaging involves the capture of low intensity light (on the order of individual photons) from a light emitting sample, and the construction of images based on the photon emission data. This source of light in the sample visually indicates the origin of the activity of interest. For example, specialized in-vivo imaging applications may include analysis of one or more representations of photon emissions from internal portions of a specimen superimposed on a photographic representation of the specimen. The luminescence representation indicates portions of the specimen where an activity of interest may be taking place. The photographic representation provides the user with a pictorial reference of the specimen.
In-vivo imaging is performed by capturing an image of the sample using a camera. Intensified or cooled charge-coupled device (CCD) cameras are often used to detect the localization of low intensity light-producing cells in the sample. These cameras are considerably complex, require specialized cooling, and are fixed to a single location on the top of a specimen chamber. A user places a sample at a predetermined position on the bottom of the specimen chamber within the field of view for the overhead camera. This static relationship between camera and sample limits image capture to overhead images only.
Often, it is desirable to capture different views of the sample. For example, the detection of internal light-producing cells from the underside of a mammalian sample may be affected by covering tissue which the light must penetrate before being captured by the overhead camera. By gathering data from different angles, a user can obtain more information about the location and intensity of a light source in the animal than possible using only a single view. However, it may be impractical to reposition the sample to capture a different view when using an overhead camera.
In view of the foregoing, an improved imaging system that enables the capture of images from different views without repositioning the posture of the sample would be highly desirable.